| 摘要 |
PROBLEM TO BE SOLVED: To provide a beam attenuation circuit which allows beam attenuation of the shift indicator with simple and less expensive constitution. SOLUTION: In this circuit, seven light emitting diodes(LED) corresponding to seven shift positions comprise an umber LED D1 and green LEDs D2 to D7. The circuit is also provided with a resistance 11 for current regulation connected between the power supply +V and the anode of the green LEDs, a resistance 12 for current regulation connected between the anode of the green LEDs and the anode of the umber LED, and a resistance 13 for beam attenuation connected to the anode of the green LEDs. When a transistor array selects one of the LEDs and a transistor 17 receives the voltage for bulbs for illumination, the current flows from the power supply +V to the transistor 17 through the resistance 11 for current regulation and the resistance 13 for beam attenuation, leading to attenuate the beam of the LED selected by the transistor array.
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